On transversality of bent hyperplane arrangements and the topological
expressiveness of ReLU neural networks
- URL: http://arxiv.org/abs/2008.09052v2
- Date: Thu, 2 Dec 2021 18:59:26 GMT
- Title: On transversality of bent hyperplane arrangements and the topological
expressiveness of ReLU neural networks
- Authors: J. Elisenda Grigsby and Kathryn Lindsey
- Abstract summary: We investigate how the architecture of F impacts the geometry and topology of its possible decision regions for binary classification tasks.
We use this obstruction to prove that a decision region of a generic, ReLU network F: Rn -> R with a single hidden layer of dimension can have no more than one bounded connected component.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Let F:R^n -> R be a feedforward ReLU neural network. It is well-known that
for any choice of parameters, F is continuous and piecewise (affine) linear. We
lay some foundations for a systematic investigation of how the architecture of
F impacts the geometry and topology of its possible decision regions for binary
classification tasks. Following the classical progression for smooth functions
in differential topology, we first define the notion of a generic, transversal
ReLU neural network and show that almost all ReLU networks are generic and
transversal. We then define a partially-oriented linear 1-complex in the domain
of F and identify properties of this complex that yield an obstruction to the
existence of bounded connected components of a decision region. We use this
obstruction to prove that a decision region of a generic, transversal ReLU
network F: R^n -> R with a single hidden layer of dimension (n + 1) can have no
more than one bounded connected component.
Related papers
- Topological obstruction to the training of shallow ReLU neural networks [0.0]
We study the interplay between the geometry of the loss landscape and the optimization trajectories of simple neural networks.
This paper reveals the presence of topological obstruction in the loss landscape of shallow ReLU neural networks trained using gradient flow.
arXiv Detail & Related papers (2024-10-18T19:17:48Z) - A rank decomposition for the topological classification of neural representations [0.0]
In this work, we leverage the fact that neural networks are equivalent to continuous piecewise-affine maps.
We study the homology groups of the quotient of a manifold $mathcalM$ and a subset $A$, assuming some minimal properties on these spaces.
We show that in randomly narrow networks, there will be regions in which the (co)homology groups of a data manifold can change.
arXiv Detail & Related papers (2024-04-30T17:01:20Z) - The Geometric Structure of Fully-Connected ReLU Layers [0.0]
We formalize and interpret the geometric structure of $d$-dimensional fully connected ReLU layers in neural networks.
We provide results on the geometric complexity of the decision boundary generated by such networks, as well as proving that modulo an affine transformation, such a network can only generate $d$ different decision boundaries.
arXiv Detail & Related papers (2023-10-05T11:54:07Z) - Neural Vector Fields: Generalizing Distance Vector Fields by Codebooks
and Zero-Curl Regularization [73.3605319281966]
We propose a novel 3D representation, Neural Vector Fields (NVF), which adopts the explicit learning process to manipulate meshes and implicit unsigned distance function (UDF) representation to break the barriers in resolution and topology.
We evaluate both NVFs on four surface reconstruction scenarios, including watertight vs non-watertight shapes, category-agnostic reconstruction vs category-unseen reconstruction, category-specific, and cross-domain reconstruction.
arXiv Detail & Related papers (2023-09-04T10:42:56Z) - Data Topology-Dependent Upper Bounds of Neural Network Widths [52.58441144171022]
We first show that a three-layer neural network can be designed to approximate an indicator function over a compact set.
This is then extended to a simplicial complex, deriving width upper bounds based on its topological structure.
We prove the universal approximation property of three-layer ReLU networks using our topological approach.
arXiv Detail & Related papers (2023-05-25T14:17:15Z) - On the Effective Number of Linear Regions in Shallow Univariate ReLU
Networks: Convergence Guarantees and Implicit Bias [50.84569563188485]
We show that gradient flow converges in direction when labels are determined by the sign of a target network with $r$ neurons.
Our result may already hold for mild over- parameterization, where the width is $tildemathcalO(r)$ and independent of the sample size.
arXiv Detail & Related papers (2022-05-18T16:57:10Z) - Local and global topological complexity measures OF ReLU neural network functions [0.0]
We apply a piecewise-linear (PL) version of Morse theory due to Grunert-Kuhnel-Rote to define and study new local and global notions of topological complexity.
We show how to construct, for each such F, a canonical polytopal complex K(F) and a deformation retract of the domain onto K(F), yielding a convenient compact model for performing calculations.
arXiv Detail & Related papers (2022-04-12T19:49:13Z) - Mean-field Analysis of Piecewise Linear Solutions for Wide ReLU Networks [83.58049517083138]
We consider a two-layer ReLU network trained via gradient descent.
We show that SGD is biased towards a simple solution.
We also provide empirical evidence that knots at locations distinct from the data points might occur.
arXiv Detail & Related papers (2021-11-03T15:14:20Z) - The Separation Capacity of Random Neural Networks [78.25060223808936]
We show that a sufficiently large two-layer ReLU-network with standard Gaussian weights and uniformly distributed biases can solve this problem with high probability.
We quantify the relevant structure of the data in terms of a novel notion of mutual complexity.
arXiv Detail & Related papers (2021-07-31T10:25:26Z) - What Kinds of Functions do Deep Neural Networks Learn? Insights from
Variational Spline Theory [19.216784367141972]
We develop a variational framework to understand the properties of functions learned by deep neural networks with ReLU activation functions fit to data.
We derive a representer theorem showing that deep ReLU networks are solutions to regularized data fitting problems in this function space.
arXiv Detail & Related papers (2021-05-07T16:18:22Z) - Provably Efficient Neural Estimation of Structural Equation Model: An
Adversarial Approach [144.21892195917758]
We study estimation in a class of generalized Structural equation models (SEMs)
We formulate the linear operator equation as a min-max game, where both players are parameterized by neural networks (NNs), and learn the parameters of these neural networks using a gradient descent.
For the first time we provide a tractable estimation procedure for SEMs based on NNs with provable convergence and without the need for sample splitting.
arXiv Detail & Related papers (2020-07-02T17:55:47Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.